Researchers have revealed that a novel virus appears to be cause of demise of three squirrel breeders in Germany after they contracted the virus from the animals. Progressive encephalitis or meningoencephalitis was developed by the three men over the course of two years, leading to their death within 2 to 4 months, said Martin Beer, DVM, of the Friedrich-Loeffler-Institut in Greifswald-Insel Riems, Germany, and colleagues.

Researchers say that a new virus dubbed as squirrel 1 bornavirus (VSBV-1) is possibly the killer of three squirrel breeders in Germany who caught it from the animals. The three men developed encephalitis or meningoencephalitis over a 2-year period.

All the men belonged to the German state of Saxony-Anhalt and they bred variegated squirrels, a species native to Central and southern North America. Many people like to keep the animal as an exotic pet in Europe.

Beer and colleagues reported in the New England Journal of Medicine that a previously unknown bornavirus was found in a contact squirrel and in brain tissue from the three men through a genomic analysis. The researchers said that bornavirus is the most possible link to their deaths.

A range of warm-blooded animals, from birds to primates are infected by known the bornavirus species. However, Beer and colleagues said that the virus is currently not believed to be a potential killer of human beings. The new virus is dubbed as variegated squirrel 1 bornavirus (VSBV-1). Beer and colleagues said that it is distinct from the other species.

"VSBV-1 is likely to be a previously unknown zoonotic pathogen transmitted by the variegated squirrel", they said.

The three apparent victims of the virus developed similar symptoms including fever, shivers, or both; progressive psychomotor slowing; confusion; unsteady gait, and myoclonus, ocular paresis, or both.